Die holder for grinding machines



- Mar. 3, 1925.

T. B. MURPHY DIE HOLDER FOR GRINDING MACHINES 3 Sheets-Sheet 1 A WmsmmFiled Dec. 12, 1925 N &

h N a SIM umber Mar. 3. 1925.

T. B. MURPHY DIE HOLDER FOR GRINDING MACHINES Filed Dec. 12, 1925 3Sheets-Sheet 2 E1 LIE-.1 U

Mar. 3, 1925.

T. B. MURPHY DIE HOLDER FOR GRINDING MACHINES 5 Sheets-Sheet 5 Filed Deo. 12, 1925 Patented Mar. 3, 1925.

UNITED STATES THOMAS B. MURPHY, OF .ALGONAC, MICHIGAN.

DIE HOLDER FOR GRINDING MACHINES.

Application filed December 12, 1923. Serial No. 680,230.

To all whom it may concern:

Be it known that I, THOMAS B. MuRrHY, a citizen of the United States,residing at Algonac, in the county of St. Clair and State of Michigan,have invented certain new and useful Improvements in Die Holders forGrinding Machines; and I do declare the following to be a full, clear,and exact description of the invention, such as will enable othersskilled in the art to which it appertains to make and use the same.

My invention relates to improvements in work holders and has referencemore particularly to a novel device for holding thread-cutting dies suchas those used in stocks, while they are being ground, the princimlobject of the invention being to provi e a simple, inexpensive andeasily operated device of this character, which may be easily attachedto the-supporting stand of an emery or other grinding wheel, theconstruction being such that both the throats and faces may be ground ondies of different sizes and makes.

A further object is to provide a unique gauge for properly setting thework-holding means, for the first die of any set, the setting for theother dies of said set, being the same.

Vith the foregoing in view, the invention resides in the novel subjectmatter hereinafter described and claimed, the description beingsupplemented by the accompanying drawings.

Figure 1 is a side elevation showingthe application of my inventiontothe stand of a grinding wheel.

Figures 2 and 3 are horizontal sectional views as indicated by lines 22and 3-3 of Fig. 1.

Figure 4 is a top plan view partly broken away and in horizontalsection.

Figure 5 is a vertical sectional view on line 5-5 of Fig. 4.

Figure 6 is a side elevation.

Figure 7 is a vertical sectional view as indicated by line 77 of Fig. 4.

Figure 8 is a similar view on line 8-8 of Fig. 4.

Figure 9 is a detail vertical section as indicated by line 99 of Figs. 4and 6.

Figure 10 is a perspective view of the gauge.

a screw or the like 2 to a horizontal ledge 3 with which the stand 4 ofa grinding wheel 5 is formed. The block 1 is formed with an openingrotatably receiving a bushing 6 into which a forwardly and rearwardlymovable slide 7 extends, and said block is split at one side of saidbushing 6, as indicated at 8, a bolt or the like 9 being provided tocontract the block about the bushing and hold the latter againstrotation after properly set. The slide is preferably of the cylindricalshape shown, and a key 10 is provided to slidably connect it to thebushing 6 so that holding the latter against turn ing, will also holdthe slide.

I have shown a collar 11 releasably clamped around the slide 7 in frontof the block 1, and a screw 12 is swiveled in said collar and isthreaded through the block for adjusting the slide forwardly orrearwardly, as occasion may demand, when the bolt or screw 9 isloosened. The front end of the screw 12 is preferably provided with ahand crank 13 by means of which it may be easily rotated.

The front end of the slide 7 has been shown as provided with an enlargedsplit head 14 having an opening 15 in which a vertical post 16 isreceived for vertical adj ustment and for rotary adjustment. A screw 17is shown for contracting the head 14 around the post 16, to hold thelatter in adjusted position. By loosening the screw 9 and the collar 11,the post 16 may be tilted to any desired extent when making necessaryadjustments preparatory to use.

The upper end of the post 16 is split and is provided with an opening 18which rotatably and slidably receives a horizontal arm 19, a screw orthe like 20 being provided to contract the split upper end of the post16, so as to hold the arm 19 in adjusted position.

Suitable graduations may be provided on any parts which are to berelatively adjusted, to aid in accurately making the necessaryadjustments.

supporting block 21 is provided with a horizontal fixed bushing 22through which the arm 19 passes slidably, a suitable key or the like 23(Fig. 7) beingprovided to hold said bushing against rotation on the arm19, so that when the latter is rotatably adjusted in the upper end ofthe post 16 and locked by tightening of the screw 20, the block 21 isheld against vertical swinging. This block is provided with a segmentaledge 24, and a bifurcated work-carrier straddles sa d block and ispivotally adjustable along said edge 24. In the present showing, thelower furcation 26 of the carrier 25, is pivoted to the lower side ofthe block 21, by av screw or the like 27, while the upper furcation 28lies upon the block 21' and is formed with an elongated recess 29 toreceive a die 30 to be ground. A slide 31 has been SlIOWII III the lowerportion of the recess 29, said slide having an upstanding pin 32 to abutthe die 30 as shown in Fig. 7 so that by adjusting a suitable screw 33for the slide 31, the latter may be operated to project the die 30 tothe proper extent (determined by a gauge hereinafter described). Abackup screw 34 is provided for the pin 32, the two screws 33 and 34being threaded through the rear end of the work-carrier 25. Both ofthese screws are preferably provided with springs 35 which are heldunder compression and will consequently hold the screws againstaccidental release. Either or both screws 33-34 may he used at one timeand if desired when using the screw 33, screw 34 may be removed.

A handle 36, is provided for turning the carrier 25 upon the pivot 27,said handle being formed with a threaded front extremity 37 which isthreaded into a radial opening 38 formed in the rear end of the carrier25, in position to allow the terminal 37 to be brought into contact withthe segmental edge 24 of the block 21, when desired. Thus, by turningthe handle 26 in one direction, the carrier 25 may be held againstpivotal movement around the screw or the like 27, while turning of saidhandle in the other direction will release its extremity 37 from thesegmental edge 24, and will permit free swinging of said carrier aboutthe pivot 27. A spring 39 is preferably provided for the handle 36,having the same function as the springs 35 above described.

I have shown a pair of contractible collars 40 and 41 011 the arm 19, tolimit the movement of the block 21 upon this arm, the collar 41 beingprovided with a spring-held adjusting screw 42 for engagement with theblock 21 and being equipped with a similar screw 43 to limit the turningof the carrier 25, in one direction.

I have made unique provision for clamping dies of different sizes in therecess 29. The upper furcation 28 of the carrier 25 is provided with aguide groove 44 which opens into one side of the recess 29 and slidablyreceives a die-clamping jaw 45, the upper side of this jaw beingpreferably provided with a resillent tongue 46 which extends beyond itto overlie the die 30 and hold it downwardly in the recess 29. The outerend of the jaw is pivotally connected by links 47 with one end of ahorizontally movable lever 48 which is fulcrumed between its endson anarm 49 extending from the carrier 25. The other end of the lever 48 ispivoted at 50 to oneend of a handle 51. This handle is in turn pivotedat 52 to a link 53 which extends toward the carrier 25, the inner end ofsaid link bein pivoted at 54 to a plunger 55 which is slidably mountedin the carrier 25, said plunger being provided with a threaded stem 56and a serrated nut 57 engaged with'said stem. By turning the nut in onedirection, the plunger 55 is forced outwardly and thus the opposite endof the lever 48 is forced inwardly, so as to cause the jaw 45 to projectfurther inwardly than otherwise, for clamping a comparatively thin die.Rotation of the nut 57 in the opposite direction. will of course adjustthe jaw 45 outwardly. Regardless of the adjustment of this jaw, when itis forced into operative position, by inward swinging of the handle 51the pivot 52 moves slightly beyond a dead center line passing throughthe pivots 50.and 54 and thus said jaw 45 is tightly held in operativeposition.

By making proper adjustments of the device, and properly dressing thegrinding wheel 5, the throat 58 of any die 30, may be ground, the handle36 being then loosened from engagement with the segmental edge 24 of theblock 21, so that the carrier 25 may be oscillated horizontally duringthe grind ing operation. By rigidly holding this carrier upon the block21, at the proper angle, the face 59 of the (lie may be ground againstone side of the wheel 5. When grinding certain forms of metric threaddies, it is necessary to remove the pin 32 and substitute one of smallersize, as will be readily understood by those skilled in the art.

The device may be easily adjusted in any desired-manner and operatedwith ease, and numerous makes and sizes of dies may be accuratelyground. In order to properly set the device for the first die of anyset, I prefer to make use of the gauge which is shown most clearly inFig. 10. This gauge com prises an elongated member 60 having an opening61 in one end to receive a pin 62 rising from the carrier 25, as shownin Fig. 7-. The other end of the member 60 is formed with an opening 63into which a pin 64 is detachably threaded. This pin is adapted forengagement with the threadcutting teeth of the die 30 as shown in dottedlines in Fig. 7 when the die is placed in the recess 29, and the opening61 is placed over the pin 62. The screw 33 is adjusted until the pin 32comes in contact with the inner end of the die 30, whereupon the backupscrew 34 may be threaded into place if both screws are being used. Thehandle 51 is of course operated to force the jaw 45 inwardly to itsoperative position. The gauge 60 may now be removed and when the firstdie is ground, it is taken out of the holder and the second one of theset inserted. This second die and all of the others of a set may beground without further adjustment of the device.

Itmay here be pointed out that pins 61 of difl'erent sizes are providedto co-operate with the dies which are used for cutting threads on stockof numerous diameters.

The general operation of the invention is as follows :With the collar 40set rather close to the post 16, and with the yoke 25 swung to the leftuntil it strikes the arm 19, and with the slide? adjusted forwardly to asufiicicnt extent by means of the" screw 12 and handle 13, place any dieof a set in the recess 29, swing the handle 51 until the jaw '25 is justtouching the die 30, engage the gauge with the pin 62, and adjust screwor 34, as occasion may dictate until the die 30 strikes the pin 64. Thegauge is then removed and the die is tightly clamped by forcing thehandle 51 to the left as far as it will go. The block 21 is now slid tothe right on the arm 19 until the die 30 is in front of the emery wheel5 and the collar 41 is adjusted to the proper point on the arm 19, andany minute adjustment required,

may be made by the screw 42. Then, the ha'ndle 13 may be moved to slidethe member 7 rearwardly to engage the throat of the die with thegrinding wheel 5 and by then loosening the handle 36 and horizontallyswmging the yoke 25, it will be seen that this throat will be accuratelyground. The movement of the yoke in one direction may be limited by thescrew 43, as desired. One die having been ground, the member 21 is slidto the left on the arm 19 after first operating the handle 13 to retractthe die from the grinding wheel. The next die of the set may then beinserted.

For grinding the face of one of the dies 30, which is not alwaysnecessary when grinding a throat, the member 21 is moved to the leftagainst the collar 40, the die is set forward in the recess 29 byturning the proper adjusting screw, the handle 36 is loosened, and theyoke 25 set at the proper angle, in which position it may be locked bytightening the handle 36, and slide the block 21 to the right until thedie 30 touches the side of the grinding wheel 5. The stop collar 41 andthe adjustable stop 42 may be used to limit the movement of the block 21and consequently control the depth of the grinding. When the face of onedie is thus ground, the block 21 is moved to the left, the ground die isremoved, another is inserted, and the operation is repeated. To grindleft-hand dies, reverse the collars 40 and 41 and also reverse the otheroperations. Whenever making adjustments, the emery wheel 5 should not bein motion.

As excellent results may be obtained from the details above described,these details are preferably followed, but within the scope of theinvention as claimed, numerous changes may be made. Also, it may here bestated that if desired, instead of supporting the block 21 andassociated parts, the arm 19 may be used, in some instances, tosupportother forms of work-holding devices. For instance, the block 22of my U. S. Patent No. 1,400,762, of Dec. 20, 1921, may be supported onthis arm if desired.

I claim:

1. A work holder comprising a main supporting block adapted to besecured to a grinding wheel stand, a horizontally adj ustable slideextending forwardly from said block, a vertically adjustable sliderising from the front end of said horizontally adjustable slide, ahorizontal arm extending from the upper end of said verticallyadjustable slide for disposition substantially parallel with thegrinding wheel axis, a. second supporting block carried by said arm, anda work holder pivoted to said second block for horizontal swinging.

2. A work holder comprising a main supporting block adapted to besecured to a. grinding wheel stand, a horizontally adjustable slideextending forwardly from said block and. having a circular verticallyformed opening, a post received in said opening for vertical and rotaryadjustments, the upper end of said post having a horizontally formedopening, a horizontal arm received in said horizontally formed openingfor rotary adjustment, a second supporting block longitudinallyadjustable but non-rotatable on said horizontal arm, and a work carrierpivoted to said second block for horizontal swinging.

3. A work holder comprising a main supporting block adapted to besecured to a grinding wheel stand, a horizontally adjustable slideextending forwardly from said block and having a vertically formedopening, a post received in said opening for. vertical and rotaryadjustments, the upper end of said post having a horizontally formedopening, a horizontal arm received. in said horizontally formed opening,a second supporting block having a hOI'lzontally formed openingreceiving said horizontal arm. and a work carrier pivoted to said secondblock for horizontal swinging, said horizontal arm and horizontalopenings permitting vertical pivoting of said second block andadjustment thereof toward and from said post.

4. A work holder comprising a body having a work-engaging abutment, aworkclamping jaw movable toward and from said abutment, a leverfulorumed between its ends on said body for movement toward and from thesame and connected at one end with said jaw, a handle pivoted to'theother end of said lever, and means associated with said handle and bodyfor outwardly forcing the former when swung in one direction, whereby tooperate said lever to force said jaw inwardly toward said abutment.

5. A work holder for a grinding machine comprising a supporting'memberhaving a segmental edge, a work carrier said supporting memberconcentrically with said edge, said carrier having an opening radiallydisposed with respect to the pivoted carrier, and a handle for freelyoscillating said carrier during one grinding operation, said handlehaving one end threaded in said opening and adapted to bind against saidsegmental edge when the handle is rotated is one direction, whereby thecarrier may be rigidly held with respect to said supporting member toperform another grinding operation.

6. A work holder comprising a supporting member having a segmental edge,a, bifurcated work carrier whose furcations straddle said supportingmember, means pivoting one of said furcations to said supporting member,work holding means associated with the other of said furcations, and anoperating handle for said work holder having an end threaded through theintermediate portion of said holder and adapted to bind against saidsegmental edge when desired.

7 A work holder comprising a supporting member, a bifurcated workcarrier whose furcations straddle said supporting member, means pivotingone furcation to said supporting member for swinging movement, the otherfurcation having a work receiving recess, and means for holding the workin said recess.

8. A work holder comprising a body having a work receiving recess, awork clamping jaw at one side of said recess, a lever fulcrumed betweenits ends on said body for movement toward and from the same andconnected at one end with said jaw, a handle pivoted to the other end ofsaid lever, and means associated with said handle and body for outwardlyforcing the former when swung in one direction, whereby to operate saidlever to force said jaw inwardly.

9. A work holder comprising a body having a work rece ving recess, awork clamping jaw at one side of said recess, a lever fulcrumed betweenits ends on said body for movement toward and from the same andconnected at one end with said jaw, a handle pivoted to the other end ofsaid lever, and a link pivotally carried by said body and pivoted at itsouter end to said lever, the pivot connecting said link and lever beingmovable beyond a dead center line intersecting the pivotal connectionbepivoted to tween the link and body and the connection between thehandle and lever, when said handle is operated to cause the lever toforce beyond the inner end of said jaw to yieldably engage the work.

12. A work holder comprising a body having a work receiving recess, awork adjusting slide at the bottom of said recess having a pin to abutthe work, and a back-up screw for said pin threaded through said body.

13. A work holder comprising a body having a work-engaging abutment, aworkclamping jaw movable toward and from said abutment, a leverfulcrumed between its ends on said body for movement toward and from thesame and connected at one end with said jaw, a handle pivoted to theother end of said lever, and a link pivotally carried by said body andpivoted at its outer end to said lever, the pivot connecting said linkand lever being movable beyond a dead center line intersecting thepivotal connection between the link and body and the connection betweenthe handle and lever, when said handle is operated to cause the lever toforce inwardly on said jaw.

14. A structure as specified in claim 13; together with means foroutwardly or inwardly adjusting the pivotal connection between the linkand said body to vary the inward movement of said jaw.

15. The combination with a grinding wheel having a flat side and arounded edge: of a holder for a thread cutting die spaced outwardly fromsaid rounded edge, and. adjusting and mounting means for said holderpermitting the throat of the die to be positioned against the roundededge of the grinding wheel and also permitting one flat side of the dieto be disposed against the flat side of the wheel, said mounting andadjusting means for the die holder including means whereby said holdermay be oscillated when the die is in one position with respect to thegrinding wheel but rigidly held when the die is in its other position.

In testimony whereof I have hereunto affixed my signature.

THOMAS B. MURPHY.

